I have the answer!!! It’s been so long, but I have a solution that will work for both Geometry Brushes and Static Mesh Actors! Confirmed works in version 4.19. Shortcuts in Windows.
Geometry:
- Group all of your actors together (Ctrl + G).
- Under Brush Settings, click on the arrow at the bottom to open the advanced settings

- Click on “Create Static Mesh”, rename to whatever you want, and save it in the folder of your choice.
Now you have a static mesh of your Geometry Brushes able to be scaled as if they were their own object.
Static Mesh:
- Group all the objects together.
- Right click, and select “Convert Actors to Static Mesh”

Like above, rename to whatever you want, and save it in the folder of your choice. Now you have a static mesh of your group meshes able to be scaled as if they were their own object.
Hope this helped people!